Harnessing Solar Energy to Reduce Dependence on Fossil Fuels - Term Paper Example

Harnessing Solar Energy to Reduce Dependence on Fossil Fuels Origin of Fossil Fuels The sun, a constant source of light and energy, is the central part of the solar system. We cannot imagine life on earth without the light, warmth and energy given out by the sun. Millions of years ago, when the solar system was in the process of evolution, numerous physical and chemical changes were taking place on the earth, both on the crust and inside the core of the earth. Various life forms evolved and perished in the process. The remains of these life forms were acted upon by the sun’s heat and light and fossils were formed. In a way, fossil fuels are also derived from the action of the sun’s energy. Fossil fuels are the fuels that have developed over millions of years through various natural processes. Thousands of centuries ago, when plants and animals perished, their fossils gradually became a part of the soil. These were pushed deeper into the earth and were acted upon by intense pressure and temperatures. Over the years, the fossils underwent slow chemical and physical changes, and gradually attained the state they possess now. The main types of fossil fuels are coal, petroleum and natural gas. Importance of Fossil Fuels Because the global economy is powered by fossil fuels, it is critical to know how long world reserves will last. However, estimating the world’s remaining fossil fuel reserves requires extensive information, including comprehensive geological maps of the world’s sedimentary basins, models of energy production systems, and data showing world energy consumption patterns and trends. When estimating the world’s fossil fuel supply, experts distinguish between reserves and resources. Reserves are fossil fuel deposits that have already been discovered and are immediately available. Resources are fossil fuel deposits that geologists believe are located in certain sedimentary basins, but have not yet been discovered. Because geologists base fossil fuel resource estimates on the location, extent, and formation of deposits recovered in geologically similar basins, resource estimates are less certain than reserve estimates. Both reserve and resource estimates are revised as data about new and existing deposits become available. Because fossil fuels are being consumed at much faster rates than they are produced in the earth’s crust, humankind will eventually deplete these nonrenewable resources. While it is unclear how far in the future this will happen, there is evidence that some regions are becoming depleted in certain types of fossil fuels. For example, production of crude petroleum in the United States peaked in 1970. Today the United States imports significantly higher proportions of its petroleum needs. Total worldwide energy consumption is expected to grow at about 2.2 percent per year until 2015. Gene Whitney, "Fossil Fuels," Microsoft® Encarta® Online Encyclopedia 2007 Today, almost everything we use, somehow depends on fossil fuels. Vehicles run on petroleum derivatives, a major chunk of the electricity we use is generated by thermal energy from burning coal, even the LPG we use for cooking comes from fossil fuels. One might wonder where the continuous supply of this wonder fuel comes from! Unfortunately, the hard facts are, fossil fuels are neither wondrous, nor do we have a continuous supply of these. Fossil Fuels and Environment Not only are these fossil fuels non-renewable, they also cause large-scale-damage to the environment. The combustion of fossil fuels results in the release of carbon dioxide and carbon monoxide in the atmosphere, which in turn pollutes the air and also results in global warming. If we continue using fossil fuels at the present rate, not only will they get depleted, the atmosphere too will become dangerous for human and animal survival in a few years. In any discussion of fossil fuels it is necessary to examine the combustion process. There are three important exothermic chemical reactions: C + O2  CO2 carbon dioxide 2H2 + O2  2H2O water S + O2  SO2 sulfur dioxide The last reaction is a consequence of the presence of sulfur with the true fuel materials of carbon and hydrogen. Sulfur dioxide (SO2) is a major pollutant, responsible for causing acid rain, when combined with water vapour in the atmosphere. Alternate Sources of Energy Nowadays many renewable energy sources are available for use, for example solar and wind energy and water power. Ironically, we still gain most of our energy from non-renewable energy sources or fossil fuels. The non-renewability of these sources will probably cause prices to rise up to a point where they are no longer economically feasible. Scientists have been considering the use of alternate means of fuels since quite a few years. The sun, being a constant source of energy has found favor with many researchers and innovators. The sun’s heat and energy can be used to replace fossil fuels in almost all walks of life. The initial costs of installing the plant to convert solar energy into a form useful for man is high, but the advantages in the long run are numerous. Solar Energy Energy from the sun travels to the earth in the form of electromagnetic radiation similar to radio waves, but in a different frequency range.  Available solar energy is often expressed in units of energy per time per unit area, such as watts per square metre  (W/m2).  The amount of energy available from the sun outside the Earth’s atmosphere is approximately 1367 W/m2; that’s nearly the same as a high power hair drier for every square meter of sunlight!  Some of the solar energy is absorbed as it passes through the Earth’s atmosphere.  As a result, on a clear day the amount of solar energy available at the Earth’s surface in the direction of the sun is typically 1000 W/m2.  At any particular time, the available solar energy is primarily dependent upon how high the sun is in the sky and current cloud conditions.  On a monthly or annual basis, the amount of solar energy available also depends upon the location.  Furthermore, useable solar energy is depends upon available solar energy, other weather conditions, the technology used, and the application. http://www.canren.gc.ca/tech_appl/index.asp?CaId=5&PgId=121 Use of Solar Energy To Replace Fossil Fuels Photovoltaic cells are used to trap the energy from the sun. This is then converted to electricity and supplied to homes. By using solar power for water heating, you can have an almost zero cost swimming pool or hot water supply. Solar panals are installed on the roof and a duct is installed. A transfer fluid is run along the duct from the panals to water, and the heat energy is exchanged between the two. So, instead of having high electric bills due to keeping your pool warm during the winter months, or if it is cold all year around, try solar powered heating systems. This same process is used to replace hot water heaters in houses. Instead of using natural gas or electricity to heat water, solar panels can be just as effective, especially in places such as Florida. If you can afford to install solar panels, you can cut your bills dramatically. http://www.energywhiz.com/9-12/gallery/site01/uses.html Solar energy can be converted directly or indirectly into other forms of energy, such as heat and electricity.  The major drawbacks of solar energy are: (1) the intermittent and variable manner in which it arrives at the earths surface and, (2) the large area required to collect it at a useful rate. http://www.eia.doe.gov/kids/energyfacts/sources/renewable/solar.html Solar energy is also frequently used on transportation signalling e.g. offshore navigation buoys, lighthouses, aircraft warning lights on pylons or structures, and increasingly in road traffic warning signals. Solar is used to power environmental and situation monitoring equipment and corrosion protection systems (based on impressing a current) for pipelines, well-heads, and bridges or other structures. As before, for larger electrical loads it can be cost effective to configure a hybrid power system that links the PV with a small diesel generator. Solars great benefit here is that it is highly reliable and requires little maintenance so its ideal in places that are hard to get to. Solar powered car A solar car is an electric vehicle powered by solar energy obtained from solar panels on the surface of the car. Solar cars combine technology typically used in the aerospace, bicycle, alternative energy and automotive industries Development of a practical solar powered car has been an engineering goal for 20 years. The center of this development is the World Solar Challenge, a biannual solar powered car race over 3021 km (1877mi) through central Australia from Darwin to Adelaide. The races stated objective is to promote research into solar-powered cars. Though there is tremendous scope for solar powered cars, solar cars are extremely light in weight, and might not confirm to safety standards required in cars. http://en.wikipedia.org/wiki/Solar_power Conclusion Thus we can conclude that solar energy can be used to replace the energy from fossil fuels, in the form of thermal, electrical and chemical energy in most fields. Though the initial investment in installing photovoltaic cells, which convert solar energy to other forms of energy is high compared to the cost of other fuels, in the long run, it would help mankind and the environment, as solar energy is a cleaner, environment friendly and renewable. When solar energy can be utilized for our heating, cooking, commuting and electricity needs, we can safely conclude that it can replace our dependency on fossil fuels. References : Gene Whitney, B.S., M.S., Ph.D. "Fossil Fuels," Microsoft® Encarta® Online Encyclopedia 2007 http://encarta.msn.com © 1997-2007 Microsoft Corporation. All Rights Reserved http://www.canren.gc.ca/tech_appl/index.asp?CaId=5&PgId=121 http://www.energywhiz.com/9-12/gallery/site01/uses.html http://en.wikipedia.org/wiki/Solar_power Read More